Cranking device for gas-engines.



W. VAN SCOTER. mmm; nnvror: ron ems warm.

APPLIOATIOK FILED PB B. 18, 1911. A 1,012, 1 16 Patented Dec. 19,1911.

2 SHEETS-SHEET 1.

Jzarzzegu l W. VAN SGOTER. GRANKING DEVICE PUB GAS ENGINES.

APPLIGATION FILED FEB. 13, 1911. 4 v

Patented Dec. 19, 1911.

2 SHEETS-SHEET 2,

` vent injury to the operator.

UNITED STATES PATENT OFFICE.

WILLIAM VAN SCOTER, OF BUFFALO, NEW YORK, ASSIGNOR 0F CINE-FOURTH TO WILLIAM J. HAYES, 0F BUFFALO, NEW YORK.

CBANKING DEVICE FOR GAS-ENGINES.

Specication of Letters Patent.

Application llled February 13, 1911.

Patented Dec. 19, 1911. Serial No. 608,274.

To all whom it may concern:

Be it known that I, WILLIAM VAN Scoren,

a citizen of the United States` residing at devices as heretofore constructed are sometimes turned backwardly very violently by what isf known as back firing of the engine and this in many cases has resulted in either breaking the limbs or otherwise injurin' the operator who is starting the engine y reason of the crank striking the operator during such backward turning movement.

-It is the object of this invention vto provide an improved cranking device for gas engines which will permit of etl'ectually starting the engine in the ordinary manner but which, during the back fire of the enine, will prevent-thestarting crank from eing turned backwardly and thereby pre- In the accompanying drawin consisting of 2 sheets: Figure 1 is a si e elevation, partly in section, of my improved cranking device. Figs. 2 and 3 are horizontal sec- *tions in the correspondingly numbered lines in Fig. Al. Fig. et 1s a fragmentary side elevation similar to Fig. 1 but showing the crank unlocked from -the starting shaft. Fig. 5 is a fragmenta perspective view showing the hub of t e starting crank. Fig. 6 is a fragmentary side elevation showing a modification-of a starting device etn bodying my invention.

Similar letters of reference indicate corresponding parts throughout the several views.

l'represents the usual starting shaft of an automobile which is journaled in a bearing 2 mounted on the front part of the frame.

3 represents a crank provided at its outer end with a handle 4 and at its inner end with a tubular hub Y5 which is mounted loosely upon the front art of the starting shaft. In rear of the liub of the starting crank Vthe startin shaft is provided with one or more coup ing pins 6 which project laterally or radially therefrom, two or such rind useful pins being referably employed and formed rom a sing e rod which issecured diametrically in the starting shaft so that its outer endsproject be ond the eriphery o f this shaft. At two iametricallly opposite places the rear or inner end of the hub of the starting crank is providedwith two recesses each of which has an easy sloping or inclined front side 7 arranged at a comparatively small angle relatively to the direction of ro-A tation of the hub and a comparatively abrupt sloping or inclined rear side orshoulder 8 arranged at a greater angle relatively to said. direction of rotation than said front side. In the rearmost position of the crank hub each of its recesses receives one of the coupling pins which latter are preferably of cylindrical form. Each of the ins engages one half of its width or near y so on the trailing side with the abruptly sloping rear shoulder of the coupling recess. The

startinghub is yieldingly held in this rear`4 ward or inward position so that the same is coupled with the pins of the starting shaft by means of a tension device consisting preferably lof a coil spring 9 surrounding the front part of the starting shaft and bearing at its inner end against the starting hu while its outer end bears against a shoulder. which is formed on the outer end of the starting shaft by means of a washer l0 secured to the outer end of the starting shaft by a screw nut 1l, as best shown in Fig. 3.

The hub of the starting crank is held in engagement with the coupling pins of the startlng shaft with suiiicient friction by the pressure of the spring 9 that upon turning the crank forwardly and pushing the same inwardly, as is usually done when starting an engine, the crank will be coupled with the starting shaft, as shown in Figs. l, 2 and 3, and cause the same to turn together and also turn the engine shaft in the same direction for starting the engine. If, however, the engine should kick or turn backwardly, due to back firing in the cylinder or the backward pressure of the coupling pins against the sloping rear shoulders of the `coupling recesses on the starting crank hub,

the latter will be moved axially forward, as shown in Fig. 4, by the wedging action of the coupling pins against the shoulders 8, thereby causing the driving shaft to be uncoupled from and turned backward independently of the crank, whereby injury to the operator is prevented.

In case the s ring 9 should hold the hub of the crank su4 ciently firm in engagement with the coupling pins as would tend to turn these parts together in a backward direction there would still be a possibility of the opcrators being injured. In order, however, to avoid the backward movement of the crank at all'times and render it absolutel impossible for the operator to be injure a ratchet mechanism is provided Awhich is interposed between the crank and an adjacent stationary part of the automobile. In the construction shown in Figs. 1-4, this ratchet or detent device comprises a ratchet disk 12 secured to the bearing 2 and provided with an annular row of teeth 13 each of which has an abrupt front side.

and an inclined rear side, and a sprin pressed pawl or dog 14 pivoted on the `hu of the starting crank and en the teeth of the ratchet disk. s the crank is turned forwardly the pawl or dog 14 trips idly over the teeth of the ratchet disk but positively prevents backward movement of operation i ward rotation ofthe pin 6 against the slopbe pushed pling ing driving shoulder 8 causes the hub 5 to orwardly lengthwise of the shaft 1, at which` time the pressure of the spring 9 is overcome, thereby permitting the -p in` 6 to clear the driving shoulder 8 andl enabling the shaft 1 to turn backwardly independently of the crank 3.4 4

The detent pawl 14 tively prevent backward rotationv of the cran 3 in casethe spring 9 should press theyshoulder 8 excessively against the cou- Instead of the ratchet mechanism shown in Figs. 1-4, that shown in Fig. 6 may be employed. This last mentioned ratchet or detent mechanism is practically a reversal "of that shown in Fig. 1 and`com rises a Vratchet disk 15 mounted on the hu rof the crank and provided lwith ,an annular row of ratchet teeth 16 eacli of which has` an in clinedfront' side andan abru t rear side, and a spring pressed pawl 1'( 'pivoted on the ging.' with driving shoulder 8 o the hub 5 is merely employed as an auxiliary, safety-device which will posibearing 18 of the starting shaft and engaging with the teeth of the ratchet disk 15.

I claim as my invention:

1. A cranking device for gas engines comprising a starting shaft adapted to be connected with the 'engine shaft and provided with a laterally projecting coupling pin, a crank mounted loosely on the starting shaft and provided with a sloping driving shoulder adapted to engage with saidpin, and al spring operating to move said crank axially and hold said shoulder yieldingly 'in engagement with said pin.

2. A cranking device for gas engines comprising a starting shaft, adapted to be connected with the engine shaftand provided with "a laterally projecting coupling pin,- a crank mounted loosely on the starting shaft and provided with a sloping driving shoulder adapted to engage with smaid pinz'and a spring surrounding the puter end Vof the starting shaft and bearing' at its inner end against the crank andA at its outerl end i against a shoulder on Vthesta'rtin shaft and operating to hold the shoulder e the .prank yieldingly `in engagement withfsaidjpin.

3. A cranking devicelfor gas engines comprising a startingshaftadpted to be connected with the engine"fslia and provided witha sloping driving shoulder adapted to engage with said pin, and a ratchet mechanism interposed between said crank and a stationary part and operating to permit forward turning movement of the crank but prevent backward turning movement thereof.

prising a starting shaft adapted to be connected with the engine shaft and provided .with a laterally pro'ecting coupling pin, a

crank mounted loos y on the starting shaft and provided-with :L sloping driving shoulsen fand provided" with a laterally projectingcoupling pin, `a' crank mounted loose y on the starting shaft p j 10'0 4. A cranking device for gas engines com-A der adapted to engage with said pin, and a ratchet mechanism interposed between said crank and a stationary part and operating to permit forward turning movement of the crank but prevent backward turning movement thereof, said ratchet mechanism comprising a disk mounted on a stationary part and provided with an annular row of ratchet teeth, and a spring pressed pawl pivoted on im i the hub of the crank and engaging with the c ratchet teeth.

Witness my hand-this-lth day of February, 1911. wn ISI'AM 'van scoren..

` Witnesses:

THEO. L. Pori, E. M. Grauen.

opies of this patent may be obtained for five cents each, ryaddressing the Commissioner hf-m,

Washington, 'D o. 

